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951.
Implementation of the European Landscape Convention requires new tools that link ecological, social and cultural dimensions in practical planning. Here, we propose connectivity as a conceptual tool to include different dimensions into landscape and spatial planning. We present a short review of the connectivity concept in relation to ecological, social and cultural dimensions and illustrate it by examples from a real landscape planning case.  相似文献   
952.
The massive migration flows from rural to urban areas in China, combined with an expected decline in the total population over the next decades, leads to two important challenges for China's housing: the growth of its urban housing stock and the shrinkage of rural housing. The rural and urban housing systems in China were analyzed using a dynamic material flow analysis model for the period 1900–2100 for several scenarios assuming different development paths for population, urbanization, housing demand per capita, and building lifetime. The simulation results indicate that new housing construction is likely to decline for several decades due to the fast growth over the past 30 years and the expected increased longevity of dwellings. Such an oscillation of new construction activity would have significant implications for the construction industry, employment, raw material demand, and greenhouse gas emissions to produce the construction materials. Policy and practical options for mitigating the negative impacts are considered.

Les flux migratoires massifs des zones rurales vers les zones urbaines en Chine, conjugués à un déclin prévu de la population totale au cours des prochaines décennies, entraînent deux défis importants pour le logement en Chine : la croissance de son parc de logements urbains et la diminution des logements ruraux. Les systèmes de logements ruraux et urbains en Chine ont été analysés en utilisant un modèle d'analyse dynamique des flux de matériaux sur la période 1900-2100 appliqué à plusieurs scénarios supposant différentes voies de développement concernant la population, l'urbanisation, la demande de logements par habitant et la durée de vie des bâtiments. Les résultats de la simulation indiquent qu'il est probable que la construction de logements neufs diminuera pendant plusieurs décennies en raison de la croissance rapide des 30 dernières années et de l'accroissement prévu de la durée de vie des logements. Une telle oscillation de l'activité de construction de logements neufs aurait d'importantes implications pour l'industrie du bâtiment, l'emploi, la demande en matières premières et les émissions de gaz à effet de serre résultant de la production des matériaux de construction. Les choix politiques et pratiques qui permettraient d'en atténuer les effets négatifs sont envisagés.

Mots clés: parcs de bâtiments, demande de constructions neuves, analyse dynamique des flux de matériaux, parc de logements, durée de vie, tendances, urbanisation, Chine  相似文献   
953.
Density differences may occur because of temperature differentials, suspended sediments, dissolved salts or other chemicals. Most of the large surface reservoirs are stably stratified throughout most, or all, of the year. One of the means of assisting the management is to allow a selective withdrawal from the reservoir. And while an intake is used for withdrawal (from the lower layer), a maximum discharge is required not allowing the uptake of the upper layer fluids. The value of the intake's vertical distance from the upper layer elevation (submergence) when the upper layer fluids begin to be drawn into the intake is known as ‘critical submergence’. In this study, the critical submergence for a circular intake pipe in a stratified body (which has different layer thickness) is investigated. Experiments were conducted on a vertically flowing downward intake pipe in a still-water reservoir. Artificial neural network (ANN) models and formulas, which are found by the theoretical analysis of critical spherical sink surface (CSSS), are used for the analysis of experimental results. The CSSS has the same centre and discharge as the intake. The ANN model and CSSS results are compared with the experimental results.  相似文献   
954.
Mundane objects and their everyday practices contain clues to the prevalent ideas and ideals of a society at a certain time; thus holding the power to decipher collective ideologies, contemporary beliefs, social norms and shared values. Bathroom fixtures are such ordinary products of the built environment that seem to be simultaneously insignificant and indispensable parts of daily life. This study is an historical analysis of the bathroom as a social space and of its fixtures as material culture. It reflects ideas and identities around the convoluted notions of modernisation and Westernisation in the Turkish context. It suggests that the values of being modern contributed to the transformation of traditional bathroom practices through spatial mechanisms and equipment. To unpack these values, the study engages the examination of oral histories, literary works, journals and flat plans as well as extant bathrooms. The research shows that the bathroom is a product of global modernity. Mediated through flats, which proliferated as a sign of contemporary living, the Western-style bathroom became the norm while its traditional counterpart became its other. This shift in perception indicates a concern for belonging to the world civilisation in the form of an aspiration toward being Western. A universal idea of modernisation pervades the ordinary domestic space of the bathroom and its everyday practices.  相似文献   
955.
Traditional architecture and associated environments created by residential buildings provide an important focus of interest in contemporary Turkey.1 1. The main thesis of this article is based upon my paper ‘Traditional Residential Architecture in Anatolia’, presented to a seminar on Conservation and Rehabilitation of Half-Timber Structures, Ankara: METU, 1989 and the doctoral thesis submitted to METU, Faculty of Architecture, Program of Restoration in 1994. The concepts have, however, been revised according to more recent surveys. They are generally accepted as physical witnesses of the past to be preserved and studied. Continuity in the traditional characteristics of the social group living in these environments has been observed in many of the extant settlements in Turkey. The reciprocal relationship between the dwelling and its owners, or users, has led to a dual definition of the ‘traditional dwelling unit’: the social unit being the ‘family’, the architectural unit the ‘dwelling’. The existing, modest-scaled, traditional dwellings in Turkey, which constitute the subject of this study, were mostly constructed after the seventeenth century, but more recent buildings exhibiting similar characteristics are also covered by the term ‘traditional’.2 2. The concepts of ‘tradition’, ‘culture’, ‘vernacular’, ‘historical’, ‘regional’, ‘pre-industrial’, ‘popular’ and ‘folk’ fall outside the limits of this study. The term ‘traditional’ has been used throughout the text; the term ‘Ottoman’ has not been adopted due to its attribution to the 1923 constitution of the Turkish Republic — it cannot, consequently, be used as reference to the continuation of tradition, which is one of the main ‘givens’ of this study. A term referring to a geographical distribution of archetype under investigation has been sought. There is an important building stock incorporating similar architectural characteristics within contemporary political boundaries of other countries, such as Iran, Bulgaria, Greece, etc., which had once formed part of the Ottoman Empire. ‘Turkey’ has not been preferred for its reference to the political boundaries of the Republican era for the same reason. Instead, another geographical term ‘Anatolia’ is considered in a widened context throughout the text to refer to a more generic concept than it implies geographically. Anatolia is considered to be the land of origin on which many cultures have emerged, generated and spread to the affected lands throughout history. Furthermore, the concentration of this study focuses specifically on extant dwellings in Anatolia. Within the confines of the term ‘traditional residential architecture in Anatolia’, there are further limitations. The origin of traditional residential architecture in Anatolia, its typological evolution, its social, cultural and/or historical aspects are not the major concerns of this study, which focuses on existing examples. A limitation of the period covered by this study accords with the construction dates of extant buildings from the seventeenth century onwards. This is an open-ended period because of the continuity in ‘traditional’ aspects in many of the settlements. The concept of ‘privacy’ serves as the basis of evaluation in analysing the interrelation of any two units. The interface of two units can be defined as an hierarchy of privacy represented sociologically by the interrelations of person/family/neighbourhood relationships and architecturally through the interrelations of room/dwelling unit/street/neighbourhood.3 3. This dwelling unit was the subject of the studio course ARCH 405 in 1989—1990, Autumn semester. The project was supervised by the author and Res.Asst. Ertu?rul Morçöl; the students were Önder Kaya, Ufuk Serin, Murat Aya?, Deniz Kutay and Gül Vanl?. This approach will include a brief summary of some previous studies of traditional residential architecture (Fig. 1).  相似文献   
956.
Numerous studies have shown that sorption of organic contaminants in soils is dominated by the natural organic carbon content (C org) of the soil. However, it is still under discussion whether sorption processes are fully reversible or whether an irreversibly sorbed contaminant fraction remains in the soil. This is especially important when considering soil remediation measures and its targets. In multi-stage sorption-desorption batch experiments with TCE, PCE, ortho-xylene and para-xylene and with the sorbents activated carbon, charcoal and a hydrophobic zeolite Y-200, the reversibility of sorption was studied. It could be shown that the structural features of the sorbents are of ample importance for the occurrence of a desorption-resistant fraction. While sorption was mainly reversible for the micro-porous zeolite Y-200 with a rigid pore network, charcoal and the activated carbon showed significant desorption hysteresis. However, following a subsequent sorption step, this fraction eventually desorbs and is re-mobilized.  相似文献   
957.
The paper reports a study of the surface and ground water in Solakl? Basin, Trabzon, from an assessment of 33 sampling points. Many of the parameters analysed are only marginally acceptable as potable water, even though the samples were collected during the wet season. The highest concentrations of contaminants were found downstream of the centres of population. The results indicate regular monitoring is required and some measures should be taken to protect the limited resources.  相似文献   
958.
In this study, bentonite originating from Turkey (Eski?ehir province) and activated carbon obtained from grapeseed were used as adsorbents for the removal of lead (Pb2+) and copper (Cu2+) ions from aqueous solutions. Experiments were performed in single- and binary-ion systems at constant temperature of 298 K and pH value of 5. In order to describe the adsorption mechanism Langmuir, Freundlich and Temkin isotherms were used. The total adsorption capacity values of adsorbents were compared. It was observed that the total adsorption capacity values were changed depending on the type of adsorbent used, type of metal ion and interaction between metal ions.  相似文献   
959.
Objectives: The aim of this in vitro study was to evaluate the effect of different desensitizers’ application on the microleakage of previously restored Class V composite resin restorations.

Materials and methods: Class V cavities were prepared on the buccal surfaces of 40 extracted human third molars. Forty box-shaped cavities were divided into four groups, based on the desensitizers used (n = 10). All teeth were restored with the same bonding agent and composite material. No desensitizer was applied in the control group. In the experimental groups, BisBlock, Gluma and Universal bonding agents were the desensitizers. The desensitizers were applied after completion of composite restorations according to manufacturers’ instructions. All specimens were then thermocycled at 5–55 °C, with a 10-s dwell time for 500 cycles. The samples were then immersed in 0.5% methylene blue dye for 24 h, sectioned into two equal halves, evaluated for microleakage using a stereomicroscope at 30× magnification and scored on a scale of 0–3. The data were analysed using the Kruskal–Wallis test at the significance level p < 0.05.

Results: There were no significant differences in microleakage after desensitizer application (p > 0.05). However, based on the obtained numerical values in our study, while the BisBlock and bonding groups showed lower microleakage at the occlusal margin, BisBlock, Gluma and bonding group showed lower microleakage at the gingival margin compared to the control group.

Conclusions: The application of desensitizers as a post-treatment option could be considered an advisable procedure to minimize microleakage.  相似文献   

960.
Purpose: The purpose of the present study was to compare the Vickers hardness numbers (VHNs), roughness numbers (RNs) and biological compatibility of glass carbomer (Glass Fill), resin-modified glass ionomer (Fuji II LC) and self-adhering flowable composite (Vertise Flow) materials. Materials and methods: Disc-shaped specimens of test materials (n = 15/group) were prepared, and VHNs and RNs were determined after 24 h. A direct contact test was used for cytotoxicity evaluation. Cell viability was measured for 24 h post-exposition with a photometric test (MTT assay; n = 16). Data were analysed using one-way analysis of variance with a post hoc Tukey’s test, the Kruskal–Wallis test and the Mann–Whitney U-test (p < 0.05). Results: Fuji II LC had the highest VHN. The VHN of Fuji II LC differed significantly from those of the other materials (p < 0.05). The RNs of Fuji II and Glass Fill were higher than that of Vertise Flow (p < 0.05). The self-adhering materials were not significantly cytotoxic compared with the control group (p > 0.05). Conclusions: The materials tested in this study showed a similar lack of cytotoxicity. The VHN of Fuji II LC was the highest, and the RN of Vertise Flow was the lowest.  相似文献   
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